Time: 11:00AM – 3:00PM

Location: Below Gross Reservoir

South Boulder Creek 08/30/2021 Photo Album

Another forecast of ninety degrees in Denver, CO had me craving a cold water wading destination. On Sunday night I checked the flows, and I stopped my research abruptly, when I learned that South Boulder Creek was tumbling along at 95 CFS. I visited the relatively close tailwater on 8/13/2021 and 08/18/2021 and enjoyed much success. Were green drakes still hatching, and could the canyon tailwater deliver similar results on August 30, 2021? There was only one way to find out. I made the trip to the Kayak Parking Lot below Gross Reservoir on Monday morning.

The temperature on the dashboard was already 71 degrees, as I pulled on my waders and assembled my Orvis Access four weight. Even though it was cooler than Denver, it was clearly going to be a warm day even in the shaded canyon tailwater. I was tempted to wet wade, but the cold bottom release water from the dam numbs my feet even with my waders on. I played it safe with waders, and of course quite a bit of perspiration was part of my hike in and out of the canyon.

Six cars besides mine occupied space in the parking lot, so I was concerned about competition and pressure, as I began the descent of the steep trail to the creek. I passed two anglers in the upper section and a pair of hikers walking a dog. In the middle section of the creek I encountered three senior fishermen with backpacks, as they congregated along the path, and that was the extent of human presence on my inbound hike. Perhaps the three gentlemen drove separately and met in the parking lot? That was the only explanation that made sense out of the comparatively few number of anglers given the presence of six cars. As one might expect, I was quite pleased to only encounter five other fishermen in spite of six cars in the parking lot.

Productive Water Type

By 11AM I was perched along the creek ready to configure my line to begin fishing. I began my day with an ice dub olive hippie stomper, prince nymph and salvation nymph. I was hoping the hippie stomper mimicked adult green drakes, the prince covered the presence of green drake nymphs, and the salvation nymph imitated the nymph stage of pale morning duns. Between 11AM and noon I landed one spunky eleven inch rainbow trout that rose and smashed the hippie stomper in some riffles of moderate depth. Needless to say the catch rate was not what I expected, but at least I was on the board.

On Display for the Crowd

After my standard lunch I resumed prospecting, and the creek structure changed, as the stream widened, and this translated to more fish holding lies with slower water velocity. In the thirty minutes after lunch I raised the fish count from one to six, and all but one were energetic rainbow trout. The salvation nymph became the main producer, and the turbulent oxygenated water perhaps explained the disproportionate quantity of pink-stripped trout.

Surprising Girth

By 12:30PM I spied a pair of natural green drakes, so in spite of enjoying a decent catch rate, I took the plunge and removed the dry/dropper arrangement and migrated to a parachute green drake. The first green drake that I knotted to my line displayed a narrow turkey flat wing and a short moose mane tail. This fly generated a couple of takes, but it was refused five times for each time a fish consumed it. I decided that the profile was too narrow, and I dug in my green drake box and extracted one of the new ones, that I tied last week. It possessed a white McFlylon wing and a clump of body-length moose mane tail fibers. The wing portrayed more bulk, and the tail was apparently a significant keying characteristic, because the trout responded in a major way to the new parachute green drake. With this fly on my tippet the fish count mounted to twenty-two. If one does the math, that is sixteen trout over two hours of fishing.

Asters Along the Creek

Featuring a Parachute Green Drake

During this time period I spotted quite a few natural green drakes; and, in fact, between two o’clock and 2:30PM, I observed more naturals than were seen during the entire time of my two previous visits. It seemed that the hatch reached a crescendo by 2:30PM and then abruptly reverted to the sporadic emergence that characterized the early afternoon time frame. The size of the trout that crushed the low floating parachute green drake was another fortuitous development, as brown trout and rainbow trout in the eleven to twelve inch range were fairly common.

Great Colors

As this fantastic fly fishing was transpiring, both my feet slid out from under me on a long angled and slippery submerged rock. I caught myself with both hands, before I fell in, but a bit of water trickled over the lip of my wader bib. Suddenly ice cold water ran down my legs and created a soggy foot bed for my woolen socks. The wet long underwear and socks actually felt fairly comfortable given the warm air temperatures. Once I gathered myself and took stock of the impact of the near dunking, I was ready to resume casting, but at this point I discovered that my lucky parachute green drake was MIA. I was not pleased and uttered a few choice words about my bout of bad luck, and then I replaced the green drake with another similar version with a poly wing and long moose mane tail. Later when I removed my waders in the parking lot, I noticed a strand of monofilament above my wading boot, and I was pleased to discover the long lost paradrake hooked into my wader cuff!

By 2:30PM the parachute drake lost its magic. The trout continued to inspect it, but most turned away in the last second in a rude lack of respect for my offering. It seemed that one out of every five looks resulted in a landed fish, with the others categorized as refusals. The number of looks were also spaced out causing my catch rate to plummet. On my previous South Boulder Creek visit, I converted to a green drake comparadun at this juncture, so I decided to execute the same ploy.

I replaced the parachute with a comparadun with a large deer hair wing profile, and suddenly the trout began to grab the size 14 fraud. Four additional trout rested in my net including a pair of twelve inch brown trout, and they all savored the green drake comparadun. Why does the parachute style work early and the comparadun late? Perhaps the low lying parachute with the long tail mimics the emerging green drakes early in the hatch? The long tail portrays a tail and trailing shuck, and in the early stages it takes longer for the drake to free itself from the nymph casing? As the air and water temperatures warm, the transition from nymph to adult speeds up; and, thus, the comparadun with its large full upright wing presents a more more fully emerged adult that fits the profile sought by the hungry trout. These are simply my own theories and not based on any scientific research.

Best Brown Trout of the Day

I landed a deeply colored brown trout at 3PM, and as I reached for my net, I realized that it was absent. I managed to release the trout without the benefit of a net, and then I tried to recollect, where I left the crucial fly fishing instrument. I removed my backpack, and inspected it to see if perhaps the ring pulled out of the handle, but the female end of the snap mechanism remained in place. This meant that I unsnapped the net to photograph and handle a trout, but I apparently never reconnected the retractor device. I waded downstream for fifty yards and surveyed the rocks on both banks and attempted to remember my last photo shoot. Alas, I never spotted the net, and I was forced to acknowledge that it was a lost item of equipment. I suspect that I disconnected it and dropped it in the water after releasing the fish, and I failed to realize that it was no longer tethered to my backpack. I mourned the loss for a bit, and then I decided to call it quits at 3:15PM. Handling and releasing trout without a net becomes proportionately more difficult, and I was not interested in harming South Boulder Creek trout.

Moderate Depth

Monday, August 30 developed into another solid day on South Boulder Creek. I landed twenty-six trout in four hours, and the fish count included a higher ratio of rainbow trout and trout that were a bit larger than my previous two visits. The green drake hatch was on time and heavier than previous emergences, and my imitations proved effective. I lost my favorite net, but I have a viable backup for future outings this week. Hopefully the green drake saga will continue for a few more weeks on South Boulder Creek, and I will be able to participate.

Fish Landed: 26